Spoilers in my answer!
SS/HG or B/W... I think I like HG better than Black because there's more story to it. The Pokemon Black story was intense, but Pokemon HeartGold had a lot more story to it, even if it was a decade old story. The point is, I had a lot more to do after
I beat the game. Plus the trainers in the after-game weren't on steroids. Seriously, there was a 15+ level difference between the final boss(es) and the regular trainers after the fact. Sure, my Pokemon owned them anyway, but that was by the skin of our teeth. Either way you cut it, a long to-do list even after you think you're done tops fancy shmancy animations and suspenseful storyline.
I don't care if the story was amazing. Pretty much the only thing I think Black had going for it was said fancy shmancy animations, cool characters, strong story, and new monsters. Beyond that, it was nothing new. Catch Pokemon. Train caught Pokemon. Beat gym leaders. Beat Elite Four. Beat final boss. Game over. HG, on the other hand, was catch Pokemon, train caught Pokemon, beat 8 gym leaders, defeat Elite Four and champion, go home, get ticket, go to other region, beat 8 gym leaders, talk to Oak, scale Mt. Silver, beat Red. And it took just as long to finish the after-story as it took to finish the main story, not to mention all the extra goodies they gave HG/SS, including (but not limited to) catching either Latios or Latias, catching all three weather legendaries, and the Celebi event.
Either way, I pick HG/SS. Maybe in the remake, they'll be clever enough to include more after-story and let Pokemon follow you?